Conventional bicycle structure is illustrated in the Reissued U.S. Pat. No. 30,547 to Belden. It includes a front wheel, back wheel, seat, frame, handle bars, and sprocket and chain propelling mechanism. FIG. 2 of the patent illustrates conventional structure which could be used at the front end of the frame to mount the front wheel and handle bars even though FIG. 2 illustrates the mounting structure of the Belden bicycle for the rear wheel.
The Belden patent disclosure includes a fork with the downwardly extending arms of the fork joined at their top end by a bridge. Extending upwardly from the bridge is a threaded body.
A lower cone circumscribing the threaded body mounts a thrust bearing which in turn engages a lower cup secured to one end of a cylindrical journal circumscribing the threaded body. The opposite end of the journal includes a second cup secured thereto to support a second thrust bearing. The second thrust bearing is held in place by an upper cone threaded to the body and locked in place by the combination of a lock washer and a lock nut.